1. Field of the Disclosure
Embodiments disclosed herein generally relate to expandable tubulars. More specifically, embodiments disclosed herein relate to an improved porous expandable tubular that is used within geologic structures, such as when drilling, completing, and producing a well.
2. Background Art
When drilling a well, such as an oil, water, and/or gas (i.e., fluid) producing well, the well may have to be formed within an unconsolidated formation. This unconsolidated formation may contain particulate matter, such as sand, in which the sand often is produced along with the fluid in the well. The sand and particulate matter produced may cause excessive wear or abrasion within the equipment (e.g., tubing, valves, pumps) used to produce the fluids within the well. For example, sand flowing through a valve of the production equipment may cause the valve to lose sealing capabilities, such as by having sand become trapped within the valve, or by having the sand abrade the seals within the valve. Therefore, it is beneficial to prevent, or to at least minimize, the production of sand, or any other particulate matter, when producing fluids in a well.
A common method used to minimize the production of particulate matter and filter out sand is by “gravel packing” the fluid producing well, such as during the completions operation of the well. When gravel packing a well, a steel screen, commonly known as a well screen, is placed within the wellbore. The annulus surrounding the screen is then packed with prepared gravel designed to prevent the passage of sand. The size of the gravel is usually the controlling design feature that prevents the passage of sand into the interior of the well screen, in which the gravel is usually larger than the sand found within the formation. For example, as shown in FIG. 1, a wellbore 100 with a gravel pack packer 102 is shown. The gravel pack packer 102 may be set in a casing 104 with a gravel pack screen 106 (i.e., well screen) placed within a perforated zone 108 of the gravel pack 102. Gravel 110 is then placed in the casing 104 and may flow into perforations 108 of the casing 104, in which the gravel 110 may minimize or eliminate sand production. Though this method is still commonly used, the gravel packing method may take up considerable area within the wellbore.
Other technology has also been developed to make it possible to expand a tubular when downhole, thereby attempting to minimize the area needed for sand control. This technology enables a tubular of a smaller diameter to be inserted downhole into a wellbore and then be expanded to a larger diameter once in place. This technique has been incorporated into tubular members, such as well screens and sand screens, to permit the passage of production fluid therethrough, but still inhibit the passage of particulate matter.
In one example, an expandable sand screen may be inserted downhole into a wellbore at the end of a string of tubulars. The initial outer diameter of this expandable sand screen may be smaller than the inner diameter of the wellbore. A wedge-shaped cone, also commonly referred to as a mandrel, is also inserted downhole with the sand screen on a separate string of tubulars, thereby having the cone moving independently of the sand screen. When the screen is then fixed within the wellbore at the proper location, the cone is urged into and through the sand screen with the tapered surface end of the cone preferably entering the sand screen tubular first. This urging of the cone through the sand screen tubular plastically expands the inner diameter of the sand screen to that generally of the outer diameter of the cone.
This type of expandable screen is useful in wells to increase proximity of the sand screen to the producing interface downhole. However, the requirement of an expansion cone to expand the tubular adds steps to the completion of a well by requiring at least one additional trip downhole with the cone attached to a string of tubulars. As such, these additional steps may be time consuming when using expandable sand screens. Further, this type of expandable screen may be limited to only certain types of environments and usages, as the expansion ratio, particle size retention, flexible formation contact, and collapse rating characteristics of these expandable screens may be limited. The current industry standard for the expansion ratio is generally 115%-150%, for the particle size retention is 140-300 microns (0.0055-0.012 inches), for the flexible formation contact 0-100 psi (0−690 kPa), and for the collapse rating is 270-1200 psi (1,860−8,270 kPa). As such, these current standards may be limited to meet the expectations of current and developing user needs. Accordingly, there exists a need for an expandable screen that improves upon these prior art screens for continued development and success within the fluid production industries.